1. Field of the Invention
This invention relates generally to an electronic musical instrument and more particularly to a parameter setting system for an electronic musical instrument for setting parameters used in generating a musical tone of desired characteristics.
2. Prior Art
In general, a musical tone generating section of an electronic musical instrument generates a musical tone in accordance with various parameters which determine various characteristics of a tone including a tone color and musical effects and which are previously set to desired values. For example, when it is required that a vibrato effect be applied to a musical tone, parameters relating to a delay, a speed and a depth of the vibrato effect must be set in advance respectively to desired values. The delay parameter determines the time period in terms of "msec" to lapse from the depression of key to the beginning of application of the vibrato effect. The speed parameter determines the cycle of the vibrato waveform. And, the depth parameter determines the amplitude of the vibrato waveform. Parameters necessary for applying other musical effects such as a tremolo, a celeste and a portamento to a musical tone must also be set to desired values previously. It would be further necessary to set parameters for determining a shape of the envelope waveform to a desired value.
With most of the conventional electronic musical instruments, when a tone color of a musical tone to be generated is selected, parameters determining tonal characteristics other than a tone color and corresponding to the selected tone color are automatically set to predetermined values. And, the freedom had been quite limited for the performer to change the parameters. Further, operating members or buttons are exclusively provided for the respective parameters so that many operating members are required to increase the number of the parameters which can be controlled by the performer. Such conventional electronic musical instrument is disclosed, for example, in Japanese Utility Model Application Laid-Open No. 56-38392.
Recently, it has developed an electronic musical instrument in which a certain operating member or members are commonly used for selectively controlling the respective different parameters and in which such parameters can be set to desired values by the performer himself as disclosed in Japanese Patent Application Laid-Open No. 60-149089. This is often called Multi-Menu System.
However, this newly developed conventional electronic musical instrument is still disadvantageous in the following respects.
When a tone color is selected by a performer through operating one of tone color selection switches, the parameter setting system is not always in a state to control the parameters corresponding or related to the selected tone color among the many states each bringing the different parameter sets into a controllable condition. Therefore, after selecting a tone color, the performer has to set the parameter setting system to a state that the parameters corresponding to the selected tone color are controllable.
Even if the parameters has been changed by the performer himself, the new parameters are not always better for the performer than the precedingly selected parameters. More specifically, it is not known to the performer whether the parameters newly selected are appropriate until the performer actually plays a music with the new parameters. Therefore, when the performer plays a music after changing the parameters by operating parameter setting buttons concerned, it is frequent that the performer knows that the parameters precedingly selected had been better than the parameters newly selected. In such a case, the performer must again operate the parameter setting buttons to restore the precedingly-selected parameters. However, such a frequent operation of the parameter setting buttons is very troublesome, and it is significantly difficult to perfectly restore the precedingly-selected parameters.
The conventional parameter setting system is so constructed that the changes of parameters for different musical effects can be achieved through a common set of switch means to minimize the number of switch means. However, the conventional parameter setting system suffers from a deficiency that the change of musical parameters can not be achieved in a quick manner.